Evaporation & Drying of water-based paints
(primer, basecoat, topcoat and clear coat)
The evaporation of water from varnishes can be significantly accelerated by heat input. Infrared systems for paint drying are significantly more responsive due to the lower thermal mass of the heating sources, which guarantees advantages in recipe changes and start-up processes.
The intensity maximum of the emitted IR radiation can be adjusted to the absorption maximum of the paint by using different types of radiators. This results in savings in terms of time and energy consumption.
If the near-surface coating layer is first crosslinked, the underlying coating can no longer evaporate unimpeded and it can lead to paint defects in form of pinholes/digester. Therefore the emission spectrum of the infrared radiator must be matched to the absorption behavior of the water-based paints, so that the paint dries directionally from below. Thus, the emergence of paint defects can be reliably avoided.
Due to the direct heating of the varnish layer, the infrared drying in the drying plant can also be applied to base material with a low maximum limit temperature (wood-based materials). The greatest potential for drying paints with infrared is the higher energy input, which means shorter heating and drying times, higher throughputs and smaller space requirements.
IR radiation is suitable for drying many types of varnish
Plastic coating: Drying and Curing of water-based paints on plastics of all kinds
When drying coatings on plastic, the rapid direct energy input of the infrared radiation, in the wavelengths of the absorption spectra of the water, ensures the warming of the water molecules. Due to this vibration excitation it comes to faster paint drying of the applied coating. The total process time is significantly reduced compared to a convective drying oven or industrial dryer.
Types of varnish: water-based varnish, fillers, primers, color primers, insulating and decorative lacquers, base coats, top coats and clear coats
Materials: PP-EPDM-T20, R-EMPP, PVC
Applications: furniture manufacturing, window profiles, automotive industry, topcoat on rotor blades, electric motors, submersible pumps, ...
Drying and curing of water-based paints on wood
The drying and hardening of the lacquers on wood is analogous to water-based lacquers on plastics.
Due to the faster removal of water, the use of infrared paint dryers results in a low fiber swelling for coatings on wooden materials. Also, a smaller grinding effort and the savings of a paint layer could partially be achieved. The gentle energy input prevents distortion, shrinkage cracks and bubbles.
Types of varnish: 1-component and 2-component water-based paints, fillers, primers, color primers, aqueous UV lacquers, stains of all color shades
Materials: wood, MDF boards, chipboard
Applications: wood and wood/aluminum window profiles, furniture production, ...
Drying plants for your application: Paint drying with infrared in the industry
IBT.InfraBioTech GmbH has extensive know-how in the field of paint processing/paint drying by means of infrared systems.
We support you in the redesign, equipping or retrofitting of your drying systems with infrared technology. When retrofitting existing paint shops results in a significant cost savings compared to the purchase of a new plant.
You might also be interested in:
- Evaporation & Drying of solvent-based paints
- Gelation & Curing of powder coatings